In the processing of molten metals, such as steel or aluminum, the metal handling apparatus such as ladles, torpedo cars, trough runners, tundishes and molds must be resistant to the molten metal, resistant to the mechanical stresses of the application, and also avoid premature heat loss from the system, so that the molten metal can be delivered to forming apparatus at the appropriate temperature.
The molten metal handling apparatus therefore comprises a material in direct contact with the molten metal, such as a hot-face, dense and hard refractory material showing excellent non-wetting characteristics to the molten metal. This material is then backed up with a layer of highly insulating refractory material, which provides the cold-face insulation for the apparatus. The higher the insulating properties and strength of the backup insulation, the thinner the backup insulation layer can be made to provide the desired performance characteristics. Thinner backup insulation permits a larger metals capacity for the molten metal handling apparatus, particularly such as a ladle or torpedo car.